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Letteratura scientifica selezionata sul tema "Frogs Evolution"

Autore: Grafiati

Pubblicato: 4 giugno 2021

Ultima modifica: 10 febbraio 2022

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Articoli di riviste sul tema "Frogs Evolution"

1

McAlpine, Donald F. "Helminth communities in bullfrogs (Rana catesbeiana), green frogs (Rana clamitans), and leopard frogs (Rana pipiens) from New Brunswick, Canada". Canadian Journal of Zoology 75, n. 11 (1 novembre 1997): 1883–90. http://dx.doi.org/10.1139/z97-818.

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Twenty-three helminth species were identified from bullfrogs, Rana catesbeiana, green frogs, R. clamitans, and leopard frogs, R. pipiens, in New Brunswick. Digeneans dominated adult helminth communities in the aquatic bullfrog and semi-aquatic green frog; nematodes were dominant in the more terrestrial leopard frog. In green frogs and leopard frogs, richness and abundance were greatest in adults; in bullfrogs, juveniles showed the greatest richness and abundance. An increase in vertebrates in the diet of adult bullfrogs influences helminth communities in bullfrogs. Where Glypthelmins quieta and nematodes, which infect the host by skin penetration, predominate in green frogs and leopard frogs, respectively, the increase in epidermal area with age probably influences helminth abundance. Adult female leopard frogs are larger than males and harbour greater numbers of helminths. Within the most heavily sampled component communities only larval digeneans, and less frequently nematodes with direct life cycles, were common (i.e., in > 50% of hosts); other taxa were generally present at prevalences of < 20% and intensities of < 10 helminths per frog. Although wetland characteristics and helminth transmission dynamics play a role in producing variation in helminth communities among sites, ontogenetic shifts in diet and sexual size dimorphism within these anuran species are important in shaping helminth communities in individual frog hosts.

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2

Woinarski, J. C. Z., S. M. Legge, L. A. Woolley, R. Palmer, C. R. Dickman, J. Augusteyn, T. S. Doherty et al. "Predation by introduced cats Felis catus on Australian frogs: compilation of species records and estimation of numbers killed". Wildlife Research 47, n. 8 (2020): 580. http://dx.doi.org/10.1071/wr19182.

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Abstract ContextWe recently estimated the numbers of reptiles, birds and mammals killed by cats (Felis catus) in Australia, with these assessments providing further evidence that cats have significant impacts on Australian wildlife. No previous studies have estimated the numbers of frogs killed by cats in Australia and there is limited comparable information from elsewhere in the world. AimsWe sought to (1) estimate the numbers of frogs killed by cats in Australia and (2) compile a list of Australian frog species known to be killed by cats. MethodsFor feral cats, we estimated the number of frogs killed from information on their frequency of occurrence in 53 cat dietary studies (that examined stomach contents), the mean number of frogs in dietary samples that contained frogs, and the numbers of cats in Australia. We collated comparable information for take of frogs by pet cats, but the information base was far sparser. Key resultsFrogs were far more likely to be reported in studies that sampled cat stomachs than cat scats. The mean frequency of occurrence of frogs in cat stomachs was 1.5%. The estimated annual per capita consumption by feral cats in Australia’s natural environments is 44 frogs, and, hence, the annual total take is estimated at 92 million frogs. The estimated annual per capita consumption by pet cats is 0.26 frogs, for a total annual kill of one million frogs by pet cats. Thirty native frog species (13% of the Australian frog fauna) are known to be killed by cats: this tally does not include any of the 51 threatened frog species, but this may simply be because no cat dietary studies have occurred within the small ranges typical of threatened frog species. ConclusionsThe present study indicated that cats in Australia kill nearly 100 million frogs annually, but further research is required to understand the conservation significance of such predation rates. ImplicationsThe present study completed a set of reviews of the impacts of cats on Australian terrestrial vertebrates. Cat predation on Australian frogs is substantial, but is likely to be markedly less than that on Australian reptiles, birds and mammals.

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3

Folt, Brian, e Craig Guyer. "Habitat-dependent effects of predatory spiders on prey frogs in a Neotropical wet forest". Journal of Tropical Ecology 37, n. 5 (16 agosto 2021): 214–21. http://dx.doi.org/10.1017/s0266467421000274.

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AbstractIn seasonal wet Neotropical forests, many studies have suggested that species-rich terrestrial frog assemblages are regulated bottom-up by the abundance of leaf litter. However, terrestrial frogs are prey to a diverse community of predators, and no studies have tested for top-down effects of predators on this or other anuran assemblages. Here, we used an extensive field dataset to model the relative contribution of food resources, microhabitat resources and predators towards the occupancy and detection of two frog species (Craugastor bransfordii and Oophaga pumilio) at La Selva, Costa Rica. Frog occupancy was most strongly influenced by predatory spiders and secondarily influenced by the abundance of leaf litter. Predators exerted stronger effects on frogs than food resources, and frogs avoided predators more as leaf litter decreased. Detection probability was elevated when predators were present. We found support for bottom-up effects of leaf litter on the terrestrial frog assemblage, but top-down effects by predators exerted stronger effects on frog occupancy and detection. Because predator avoidance varied along a resource gradient, predator and resource effects appear to be dependent, supporting interactions between top-down and bottom-up mechanisms. Climate-driven decreases in leaf litter may drive decreased availability of frog refugia and increased interactions between frogs and predators.

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4

Paluh, Daniel J., Edward L. Stanley e David C. Blackburn. "Evolution of hyperossification expands skull diversity in frogs". Proceedings of the National Academy of Sciences 117, n. 15 (27 marzo 2020): 8554–62. http://dx.doi.org/10.1073/pnas.2000872117.

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Frogs (Anura) are one of the most diverse vertebrate orders, comprising more than 7,000 species with a worldwide distribution and extensive ecological diversity. In contrast to other tetrapods, frogs have a highly derived body plan and simplified skull. In many lineages of anurans, increased mineralization has led to hyperossified skulls, but the function of this trait and its relationship with other aspects of head morphology are largely unexplored. Using three-dimensional morphological data from 158 species representing all frog families, we assessed wide-scale patterns of shape variation across all major lineages, reconstructed the evolutionary history of cranial hyperossification across the anuran phylogeny, and tested for relationships between ecology, skull shape, and hyperossification. Although many frogs share a conserved skull shape, several extreme forms have repeatedly evolved that commonly are associated with hyperossification, which has evolved independently more than 25 times. Variation in cranial shape is not explained by phylogenetic relatedness but is correlated with shifts in body size and ecology. The species with highly divergent, hyperossified skulls often have a specialized diet or a unique predator defense mechanism. Thus, the evolution of hyperossification has repeatedly facilitated the expansion of the head into multiple new shapes and functions.

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5

McCAY, MICHAEL G. "AERODYNAMIC STABILITY AND MANEUVERABILITY OF THE GLIDING FROG POLYPEDATES DENNYSI". Journal of Experimental Biology 204, n. 16 (15 agosto 2001): 2817–26. http://dx.doi.org/10.1242/jeb.204.16.2817.

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SUMMARY Gliding has evolved independently in two families of tree frog. Tree frogs glide to descend rapidly to mating sites over temporary pools on the forest floor or to escape predators. The physical mechanisms used by frogs to glide and maneuver were investigated using a combination of observations of live frogs (Polypedates dennysi) gliding in a tilted wind-tunnel and aerodynamic forces and torques measured from physical models of tree frogs in a wind-tunnel. Tree frogs maneuvered in the tilted wind-tunnel using two different turning mechanisms: a banked turn (the frog rolls into the turn) and a crabbed turn (the frog yaws into the turn). Polypedates dennysipossessed overall weak aerodynamic stability: slightly stable about the pitch and roll axis, slightly unstable about the yaw axis. The maneuverability of gliding tree frogs was quantified using a maneuverability index. The maneuverability of tree frogs was roughly equivalent for tree frogs performing a banked turn and performing a crabbed turn. The maneuverability of tree frogs was approximately one-third of the maneuverability of a falcon (Falcon jugger).

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6

Smith, Lora L., Jennifer M. Howze, Jennifer S. Staiger, Eric R. Sievers, Deborah Burr e Kevin M. Enge. "Added Value: Gopher Tortoise Surveys Provide Estimates of Gopher Frog Abundance in Tortoise Burrows". Journal of Fish and Wildlife Management 12, n. 1 (27 ottobre 2020): 3–11. http://dx.doi.org/10.3996/jfwm-20-030.

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Abstract The gopher frog Lithobates capito is one of the most terrestrial frogs in the southeastern United States and often inhabits gopher tortoise burrows Gopherus polyphemus outside of the breeding season. Gopher frog populations have declined, and the species is under review for listing as threatened or endangered under the U.S. Endangered Species Act. Much of our knowledge on the status of gopher frogs is based on detections of larvae at breeding wetlands, which can be challenging because of environmental variability and provides no information on the terrestrial life stages of the species. Therefore, an alternative method is called for. We recorded observations of gopher frogs during gopher tortoise surveys at four conservation lands in Florida and used line-transect distance sampling to estimate frog abundance. We also recorded burrow size, incidence of frog co-occupancy with tortoises, and distance from frog-occupied burrows to breeding wetlands. We observed 274 gopher frogs in 1,097 tortoise burrows at the four sites. The proportion of burrows occupied by gopher frogs among sites ranged from 0.17 to 0.25. Gopher frog abundance in tortoise burrows was 742 (512–1,076 95% CL) at Etoniah Creek State Forest, 465 (352–615) at Ft. White Wildlife Environmental Area, 411 (283–595) at Mike Roess Gold Head Branch State Park, and 134 (97–186) at Watermelon Pond Wildlife Environmental Area. We observed up to four frogs in a single burrow. The proportion of frogs detected in burrows occupied by a gopher tortoise ranged from 0.46 to 0.79 among sites, and overall, gopher frogs preferred burrows occupied by tortoises over unoccupied burrows (χ2 = 15.875; df = 3; P = 0.001). Gopher frogs used burrows from 7 to 43 cm in width; mean width of frog-occupied burrows did not differ from that of unoccupied burrows (F1,3 = 0.049, P = 0.825). Distance from frog-occupied tortoise burrows to the nearest breeding wetland ranged from 141 to 3,402 m. Our data on gopher frogs collected in conjunction with gopher tortoise monitoring efforts using line-transect distance sampling and burrow cameras provided novel information on frog abundance in their terrestrial habitat and required no additional effort. However, the extent to which frogs use tortoise burrows relative to other available refuges (small mammal burrows, stumps, or other structures) is unknown; thus, our estimates should be considered conservative. We suggest that terrestrial abundance estimates for gopher frogs can complement efforts to monitor breeding activity to provide a more comprehensive means of monitoring population trends in this cryptic species.

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7

Rhebergen, F., R. C. Taylor, M. J. Ryan, R. A. Page e W. Halfwerk. "Multimodal cues improve prey localization under complex environmental conditions". Proceedings of the Royal Society B: Biological Sciences 282, n. 1814 (7 settembre 2015): 20151403. http://dx.doi.org/10.1098/rspb.2015.1403.

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Predators often eavesdrop on sexual displays of their prey. These displays can provide multimodal cues that aid predators, but the benefits in attending to them should depend on the environmental sensory conditions under which they forage. We assessed whether bats hunting for frogs use multimodal cues to locate their prey and whether their use varies with ambient conditions. We used a robotic set-up mimicking the sexual display of a male túngara frog ( Physalaemus pustulosus ) to test prey assessment by fringe-lipped bats ( Trachops cirrhosus ). These predatory bats primarily use sound of the frog's call to find their prey, but the bats also use echolocation cues returning from the frog's dynamically moving vocal sac. In the first experiment, we show that multimodal cues affect attack behaviour: bats made narrower flank attack angles on multimodal trials compared with unimodal trials during which they could only rely on the sound of the frog. In the second experiment, we explored the bat's use of prey cues in an acoustically more complex environment. Túngara frogs often form mixed-species choruses with other frogs, including the hourglass frog ( Dendropsophus ebraccatus ). Using a multi-speaker set-up, we tested bat approaches and attacks on the robofrog under three different levels of acoustic complexity: no calling D. ebraccatus males, two calling D. ebraccatus males and five D. ebraccatus males. We found that bats are more directional in their approach to the robofrog when more D. ebraccatus males were calling. Thus, bats seemed to benefit more from multimodal cues when confronted with increased levels of acoustic complexity in their foraging environments. Our data have important consequences for our understanding of the evolution of multimodal sexual displays as they reveal how environmental conditions can alter the natural selection pressures acting on them.

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DeMarchi, Joseph A., Andrew Britton, Kaylee O'Donnell e Ralph A. Saporito. "Behavioural preference for low levels of UV-B radiation in two neotropical frog species from Costa Rica". Journal of Tropical Ecology 34, n. 5 (6 agosto 2018): 336–40. http://dx.doi.org/10.1017/s0266467418000287.

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Abstract:Tropical frogs experience damaging effects from exposure to UV-B radiation, and some diurnally active, conspicuous species exhibit avoidance behaviours to high levels of UV-B. To determine if similar behaviours are present in other diurnal frogs, we experimentally compared UV-B avoidance in two common species of neotropical diurnal frogs – Oophaga pumilio, an aposematic poison frog and Craugastor bransfordii, a cryptic leaf-litter frog – in response to different levels of UV-B. Wild-caught frogs were tested in experimental arenas fitted with filters that permitted two different levels of UV-B (low: 14% vs. high: 84% UV-B). Both species spent significantly more time under the low UV-B filter, suggesting that behavioural preferences for lower levels of UV-B are common to different diurnal species. Furthermore, male O. pumilio significantly preferred lower levels of UV-B, whereas females did not exhibit a preference for lower UV-B, which may suggest differences in UV-B exposure or sensitivity and/or alternative mechanism(s) to avoid UV-B between sexes. Although limited in scope, the findings of our study suggest that UV-B avoidance may be a behavioural adaptation common to all diurnal frogs.

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Tokita, Masayoshi, e Noriko Iwai. "Development of the pseudothumb in frogs". Biology Letters 6, n. 4 (10 febbraio 2010): 517–20. http://dx.doi.org/10.1098/rsbl.2009.1038.

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Frogs have highly conserved hand and foot morphology, possessing four fingers and five toes. As an exception, two Japanese ranid frog species, the Otton frog Babina subaspera and the dagger frog Babina holsti , possess a unique thumb-like structure (the pseudothumb) in the forelimb, giving an appearance of a total of five fingers on the hand. To obtain insights into the developmental mechanisms that generate this novel character, we investigated the hand morphogenesis of the Otton frog. The unique morphological pattern of the pseudothumb was already established in juveniles. Surprisingly, the bud-like structure, which is similar to the area of inductive activity (e.g. feather buds in birds and the carapacial ridge in turtles), was detected over the site where the future prepollex develops in larvae. By contrast, this bud-like structure was not found in larvae of other ranid species. We discuss possible scenarios that would favour the evolution of this very unusual trait in frogs.

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Feng, Yan-Jie, David C. Blackburn, Dan Liang, David M. Hillis, David B. Wake, David C. Cannatella e Peng Zhang. "Phylogenomics reveals rapid, simultaneous diversification of three major clades of Gondwanan frogs at the Cretaceous–Paleogene boundary". Proceedings of the National Academy of Sciences 114, n. 29 (3 luglio 2017): E5864—E5870. http://dx.doi.org/10.1073/pnas.1704632114.

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Frogs (Anura) are one of the most diverse groups of vertebrates and comprise nearly 90% of living amphibian species. Their worldwide distribution and diverse biology make them well-suited for assessing fundamental questions in evolution, ecology, and conservation. However, despite their scientific importance, the evolutionary history and tempo of frog diversification remain poorly understood. By using a molecular dataset of unprecedented size, including 88-kb characters from 95 nuclear genes of 156 frog species, in conjunction with 20 fossil-based calibrations, our analyses result in the most strongly supported phylogeny of all major frog lineages and provide a timescale of frog evolution that suggests much younger divergence times than suggested by earlier studies. Unexpectedly, our divergence-time analyses show that three species-rich clades (Hyloidea, Microhylidae, and Natatanura), which together comprise ∼88% of extant anuran species, simultaneously underwent rapid diversification at the Cretaceous–Paleogene (K–Pg) boundary (KPB). Moreover, anuran families and subfamilies containing arboreal species originated near or after the KPB. These results suggest that the K–Pg mass extinction may have triggered explosive radiations of frogs by creating new ecological opportunities. This phylogeny also reveals relationships such as Microhylidae being sister to all other ranoid frogs and African continental lineages of Natatanura forming a clade that is sister to a clade of Eurasian, Indian, Melanesian, and Malagasy lineages. Biogeographical analyses suggest that the ancestral area of modern frogs was Africa, and their current distribution is largely associated with the breakup of Pangaea and subsequent Gondwanan fragmentation.

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Più fonti

Tesi sul tema "Frogs Evolution"

1

Kulkarni, Saurabh S. "Endocrine Mechanisms Underlying Phenotypic Evolution in Frogs". University of Cincinnati / OhioLINK, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1342106009.

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2

Havens, Sarah Beth. "The role of skeletal development in body size evolution of two North American frogs". Diss., Rolla, Mo. : Missouri University of Science and Technology, 2010. http://scholarsmine.mst.edu/thesis/pdf/Havens_2010_09007dcc807be556.pdf.

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Thesis (M.S.)--Missouri University of Science and Technology, 2010.
Vita. The entire thesis text is included in file. Title from title screen of thesis/dissertation PDF file (viewed June 7, 2010) Includes bibliographical references.

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3

Dziminski, Martin A. "The evolution of variable offspring provisioning". University of Western Australia, 2005. http://theses.library.uwa.edu.au/adt-WU2005.0134.

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Most theoretical models predict an optimal offspring size that maximises parental fitness. Variation in the quality of the offspring environment can result in multiple offspring size optima and therefore variation of offspring provisioning can evolve. Variation in offspring provisioning is common and found across a variety of taxa. It can be defined as between populations, explained by optimality models, or between and within individuals, neither so easily explained by optimality models. My research focused on the evolution of variable offspring provisioning by testing theoretical models relating to variation in offspring provisioning between and within individuals. Using comparative methods, I found a positive relationship between intraclutch variation in offspring provisioning and variation in the quality of the offspring environment in a suite of pond breeding frogs. This positive relationship provided evidence that patterns of variable offspring provisioning are related to the offspring environment. This study also identified a species (Crinia georgiana) with high variation in offspring provisioning on which to focus further investigations. High variation in offspring provisioning occured between and within individuals of this species independent of female phenotype and a trade-off in offspring size and number existed. In laboratory studies, increased yolk per offspring led to increased fitness per offspring. Parental fitness calculations revealed that in high quality conditions production of small more numerous offspring resulted in higher parental fitness, but in lower quality conditions the production of large offspring resulted in the highest parental fitness. This was confirmed in field experiments under natural conditions using molecular markers to trace offspring to clutches of known provisioning, allowing me to measure exact parental fitness. The strategy of high variation in offspring size within clutches can be of benefit when the future of the offspring environment is not known to the parents: as a form of bet-hedging. Further study of the offspring environment revealed that conditions such as density dependent fitness loss, spatial variation in habitat quality, and non-random offspring dispersal, can combine to create the conditions predicted by theoretical models to maintain a strategy of variable offspring provisioning in the population. My research provides a comprehensive empirical test of the theory of variable offspring provisioning

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4

Boyd, Jonathan Lomax. "Evolutionary Analysis of the Glutamic Acid Decarboxylase 67 Immediate Upstream Region in African Clawed Frogs". W&M ScholarWorks, 2009. https://scholarworks.wm.edu/etd/1539626884.

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Vacher, Jean-Pierre. "Diversification in the Guiana Shields as seen through frogs". Thesis, Toulouse 3, 2017. http://www.theses.fr/2017TOU30063/document.

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Le Plateau des Guyanes a été géologiquement stable au cours de l'ère Cénozoïque, exempt de l'influence de l'orogénèse des Andes et de la mise en place du bassin de l'Amazone. Cette région est-elle biogéographiquement homogène au sein de l'Amazonie ? Quelles sont les modalités spatio-temporelles de diversification au sein de cette région ? Afin de répondre à ces questions, j'ai exploré sa biorégionalisation sur la base de la distribution des amphibiens anoures. Cette approche a permis de définir trois biorégions dans l'est du Plateau des Guyanes, et de révéler une forte sous-estimation de l'endémisme. Ensuite, j'ai étudié les patrons de diversification au sein du genre endémique Anomaloglossus. Ce volet a permis de dévoiler l'existence de spéciation cryptique au sein du genre, avec un patron biogéographique composé de quatre zones de diversification au sein du Plateau des Guyanes et une origine du genre dans les tepuis
The Guiana Shield has been geologically stable during the Cenozoic era, exempt of the influence of the uplift of the Andes and the setting up of the Amazon basin. Is this region biogeographically homogeneous within Amazonia? What are the spatio-temporal diversification modalities within this region? To answer these questions, I explored bioregionalisation within Amazonia and the Guiana Shield based on the dis- tribution of anuran amphibians. This approach enabled to define three bioregions in the eastern Guiana Shield and to reveal a high underestimation of endemism. Then, I studied the diversification patterns within the endemic frog genus Anomaloglossus. This part en- abled to reveal cryptic speciation within the genus, and a biogeographic pattern composed of four areas of diversification in the Guiana Shield, with an origin of the genus in the western highlands (tepuis)

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Cambridge, Tucker. "Species Distribution and Conservation Genetics of the Upland and Midland Chorus Frogs (Pseudacris) in Kentucky". TopSCHOLAR®, 2018. https://digitalcommons.wku.edu/theses/3063.

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The upland (Pseudacris feriarum) and midland (P. triseriata) chorus frogs are closely related cryptic species that are best distinguished genetically. The distribution of these species within the Commonwealth of Kentucky has previously been defined by only a handful of genetic samples, making delineation of range limits for each species difficult. Accurate understanding of species distributions, and the genetic structure within them, are vitally important for conservation management of amphibian species. In this study, I have collected genetic samples from across the putative ranges of P. triseriata and P. feriarum in Kentucky and used next-generation sequencing technology to generate more fine-scale estimates of species ranges. The genetic data generated in this study support the delineation of two species in Kentucky, and the species assignments of all individuals and populations are in general concordance with the previously hypothesized species distributions. However, I have identified two previously unrecognized contact zones for these species and revealed areas of hybridization. By delineating species distributions and identifying potentially important regions of genetic admixture, this study will be informative to future conservation management and conservation genetic research of chorus frogs in Kentucky.

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Jennions, Michael D. "Signalling and sexual selection in animals and plants". Thesis, University of Oxford, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.670250.

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Benavides, Edgar. "Evolution in Neotropical Herpetofauna: Species Boundaries in High Andean Frogs and Evolutionary Genetics in the Lava Lizard Genus Microlophus (Squamata: tropiduridae): A History of Colonization and Dispersal". Diss., CLICK HERE for online access, 2006. http://contentdm.lib.byu.edu/ETD/image/etd1652.pdf.

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Zeyl, Clifford. "Genome evolution in the primitive frog Leipelma hochstetteri". Thesis, McGill University, 1991. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=59969.

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The primitive New Zealand frog Leiopelma hochstetteri shows exceptional karyotypic variation. On the North Island, females carry univalent W chromosome and both sexes have 0 to 15 supernumerary chromosomes. Frogs from Great Barrier Island have a conventional 2n = 22 karyotype, with no sex chromosome differentiation in C-banded mitotic chromosomes. However, the lampbrush chromosomes of a Great Barrier Island female show evidence of heterogamety. This suggests that presumed ancestral female heterogamety has persisted on Great Barrier Island and given rise to a WZZ-female/ZZ-male sex chromosome system on the North Island.
A repeated sequence, Lh1, varies greatly within populations in copy number and distribution on genomic EcoRI fragments. In situ hybridization revealed the variable presence of large Lh1 arrays on supernumerary chromosomes and two autosomes. The extensive Lh1 variability implies that, like the supernumeraries, it is more selfish than functional in the L. hochstetteri genome.

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Ruiz-Linares, Andres. "Processes of molecular evolution of the rDNA multigene family in Drosophila". Thesis, University of Cambridge, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.239189.

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Più fonti

Libri sul tema "Frogs Evolution"

1

Frogs, flies, and dandelions: Speciation--the evolution of new species. Oxford: Oxford University Press, 2001.

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ill, Mazellan Ron, e Burke Dianne O'Quinn ill, a cura di. Why is a frog not a toad? Los Angeles: Lowell House Juvenile, 1992.

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Frogs Flies and Dandelions: The Making of Species. Oxford University Press, 2002.

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The Mystery Of Darwins Frog. Boyds Mills Press, 2013.

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Brown, Rafe M. Systematic evolution in the Rana signata complex of Philippine and Bornean stream frogs: Huxley's modification of Wallace's line reconsidered at the Oriental-Australian faunal zone interface. 1997.

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Kemp, T. S. Amphibians: A Very Short Introduction. Oxford University Press, 2021. http://dx.doi.org/10.1093/actrade/9780198842989.001.0001.

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Amphibians: A Very Short Introduction discusses amphibian evolution, adaptations, and biology. From frogs, toads, newts, and salamanders, to the lesser-known caecilians, there are over 8,000 species of amphibians alive today. Characterized by their moist, naked skin and the tadpole phase of their lives, they are uniquely adapted to occupy the interphase habitat between freshwater and land. This VSI explores topics from their complex courtship behaviour to how their permeable skin enables them to thrive in their habitat and it covers the whole history of amphibians, from their origins 360 million years ago, to the extinction threat they face from humans today.

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Webb, EK, a cura di. Windows on Meteorology. CSIRO Publishing, 1997. http://dx.doi.org/10.1071/9780643101500.

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Windows on Meteorology: Australian Perspective answers a host of questions about Australia's weather and climate, and explains the underlying causes of floods, droughts and cyclones. Vivid accounts of dust storms and the mysteries of the 'morning glory' cloud lines are revealed.The book highlights the perception in Aboriginal culture of the connection between seasons and natural cycles, through aspects of Aboriginal mythology and language, and contains a unique Aboriginal seasonal calendar. The influence of climate on Australia's wildlife is illustrated with fascinating accounts of the evolution of burrowing frogs, shrimps and desert kangaroos. A history of Australian meteorology from early European settlement onwards, covers subjects such as a nineteenth century view of the links between climate and health, the development of instruments, cloud physics research and the Southern Oscillation connection. The final chapters bring the reader up to date with the most recent technical developments in research and applications such as satellite remote sensing, radar and fast response instruments.

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Grimm, Jacob and Wilhelm. Selected Tales. Tradotto da Joyce Crick. Oxford University Press, 2009. http://dx.doi.org/10.1093/owc/9780199555581.001.0001.

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‘Once upon a time in mid-winter, when the snowflakes were falling from the sky like down, a queen was sitting and sewing at a window ...’The tales gathered by the Grimm brothers are at once familiar, fantastic, homely, and frightening. They seem to belong to no time, or to some distant feudal age of fairytale imagining. Grand palaces, humble cottages, and the forest full of menace are their settings; and they are peopled by kings and princesses, witches and robbers, millers and golden birds, stepmothers and talking frogs. Regarded from their inception both as uncosy nursery stories and as raw material for the folklorist the tales were in fact compositions, collected from literate tellers and shaped into a distinctive kind of literature. This translation mirrors the apparent artlessness of the Grimms, and fully represents the range of less well-known fables, morality tales, and comic stories as well as the classic tales. It takes the stories back to their roots in German Romanticism and includes variant stories and tales that were deemed unsuitable for children. In her fascinating introduction, Joyce Crick explores their origins, and their literary evolution at the hands of the Grimms.‘

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Notebook, Mainesun. Composition Notebook: Evolution Cousin Frog for Dark Garments - 50 Sheets, 100 Pages - 6 X 9 Inches. Independently Published, 2020.

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Capitoli di libri sul tema "Frogs Evolution"

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Jacobs, David Steve, e Anna Bastian. "Co-evolution Between Bats and Frogs?" In Predator–Prey Interactions: Co-evolution between Bats and Their Prey, 89–106. Cham: Springer International Publishing, 2016. http://dx.doi.org/10.1007/978-3-319-32492-0_6.

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Plötner, Jörg, Thomas Uzzell, Peter Beerli, Çiğdem Akın, C. Can Bilgin, Cornelia Haefeli, Torsten Ohst et al. "Genetic Divergence and Evolution of Reproductive Isolation in Eastern Mediterranean Water Frogs". In Evolution in Action, 373–403. Berlin, Heidelberg: Springer Berlin Heidelberg, 2010. http://dx.doi.org/10.1007/978-3-642-12425-9_18.

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Griffith, Robert W. "Guppies, toadfish, lungfish, coelacanths and frogs: a scenario for the evolution of urea retention in fishes". In Developments in environmental biology of fishes, 199–218. Dordrecht: Springer Netherlands, 1991. http://dx.doi.org/10.1007/978-94-011-3194-0_13.

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Roberts, J. Dale, e Danielle Edwards. "The Evolution, Physiology and Ecology of the Australian Arid-Zone Frog Fauna". In On the Ecology of Australia’s Arid Zone, 149–80. Cham: Springer International Publishing, 2018. http://dx.doi.org/10.1007/978-3-319-93943-8_7.

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Chartrel, Nicolas, Hubert Vaudry e J. Michael Conlon. "Primary structures of frog NPY and PYY: Implication for the molecular evolution of the pancreatic polypeptide family". In Peptides 1992, 719–20. Dordrecht: Springer Netherlands, 1993. http://dx.doi.org/10.1007/978-94-011-1470-7_328.

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Bogart, James P. "The Influence of Life History on Karyotypic Evolution in Frogs". In Amphibian Cytogenetics and Evolution, 233–58. Elsevier, 1991. http://dx.doi.org/10.1016/b978-0-12-297880-7.50015-9.

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Tymowska, Janina. "Polyploidy and Cytogenetic Variation in Frogs of the Genus Xenopus". In Amphibian Cytogenetics and Evolution, 259–97. Elsevier, 1991. http://dx.doi.org/10.1016/b978-0-12-297880-7.50016-0.

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"Phylogenetic Inference and the Evolution of Communication in Tungara Frogs". In The Design of Animal Communication. The MIT Press, 2003. http://dx.doi.org/10.7551/mitpress/2359.003.0023.

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Schulkin, Jay. "Bird Brains, Social Contact, and Song". In Reflections on the Musical Mind. Princeton University Press, 2013. http://dx.doi.org/10.23943/princeton/9780691157443.003.0003.

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This chapter examines the evolution of bird brain, social contact, and birdsong. Communicative capabilities are widespread, whether in song or through other forms of intimate social contact. One mechanism for this is the regulation of information molecules in the brain such as vasopressin and oxytocin. The chapter first provides an overview of information molecules before connecting these processes to song in frogs, crickets, and birds. It then considers neurogenesis and how information molecules work in the human brain, focusing on some core biology underlying animal song and social contact. It shows that steroid hormones facilitate neuropeptide expression in many species, which underlies song tied to the regulation of the internal milieu, territorial expression, reproduction, and a much wider range of social behaviors.

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Palaoro, Alexandre V., e Martin Thiel. "“The Caring Crustacean”: An Overview of Crustacean Parental Care". In Reproductive Biology, 115–44. Oxford University Press, 2020. http://dx.doi.org/10.1093/oso/9780190688554.003.0005.

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Many crustacean species are known to provide parental care, with behaviors ranging from ventilating the eggs to providing food for young. This chapter provides an overview of parental care patterns across crustaceans, and then compares crustacean parental care to that of select other taxa (insects, fishes, frogs) that share important traits with crustaceans (exoskeleton, aquatic or amphibious lifestyle, respectively). The aim is to identify gaps in the understanding of the evolution of parental care in crustaceans. We show that nearly all crustaceans provide parental care for early embryos (eggs), while caring for advanced stages is rarer. The most common forms of care are simple behaviors (e.g. fanning and cleaning behaviors), while complex behaviors (e.g. feeding the young) evolved exclusively in groups that also care for longer. Caring is most frequently done by females, while biparental is rare, and exclusive paternal care is nonexistent. When compared across taxa, simple behaviors are also the most common forms of care, and reasons for the evolution of parental care have common themes. First, parental care enhances offspring survival. In crustaceans, early embryo/egg mortality is apparently high, which might have triggered the evolution of parental care in several crustacean taxa independently. Second, crustaceans that have large eggs and inhabit stable habitats tend to care for longer. Lastly, internal fertilization seems to prevent male crustaceans from caring by not allowing the males to access the eggs and to ensure paternity.

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Atti di convegni sul tema "Frogs Evolution"

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Davis, Jenna, Patrick Vallely, Mayorkinos Papaelias e Zheng Huang. "Addressing Future Rail Network Performance Challenges Through Effective Structural Health Monitoring". In 2018 Joint Rail Conference. American Society of Mechanical Engineers, 2018. http://dx.doi.org/10.1115/jrc2018-6115.

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Operational efficiency is one of the key performance indicators for all railroad systems. Infrastructure inspection and maintenance engineers are tasked with the responsibility of ensuring the reliability, availability, maintainability and safety of the railroad network. However, as rolling stock traffic density increases throughout the network, inspection and maintenance opportunities become less readily available. Inspection and maintenance activities normally take place at night, when there is little or no train movement to avoid disruption of normal railroad network operation. In addition, conventional inspection methodologies fail to deliver the efficiency required for the optimization of maintenance decisions, particularly with respect to track renewals, due to their defect detection sensitivity and level of resolution limitations. The fact that critical structural components such as rails and crossings (frogs) are randomly loaded increases the degree of uncertainty when trying to estimate their remaining service lifetime. Maintenance decisions are predominantly based on the feedback received from inspection engineers, coupled with empirical knowledge that has been gained over the years. The use of structural degradation models is too risky due to the uncertainty arising from the variable dynamic loads sustained by the rail track. The use of structural health monitoring techniques offers significant advantages over conventional approaches. First of all, it is non-intrusive and does not interrupt normal rail traffic operations. Secondly, defects can be detected and evaluated in real-time whilst their evolution can be monitored continuously, enabling maintenance to be scheduled in advance and at times where the need for rail network availability at the section concerned is at its lowest. This paper analyzes the potential risks and benefits of a gradual shift from traditional inspection approaches to advanced structural health monitoring techniques.

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Tang, Deyu, Jin Yang e Xianfa Cai. "Grid Task Scheduling Strategy Based on Differential Evolution-Shuffled Frog Leaping Algorithm". In 2012 International Conference on Computer Science and Service System (CSSS). IEEE, 2012. http://dx.doi.org/10.1109/csss.2012.426.

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Li, Zhifu, Junhai Zeng e Yun Zhong. "An improved moth-flame algorithm based on differential evolution and shuffled frog leaping algorithm". In 2019 Chinese Automation Congress (CAC). IEEE, 2019. http://dx.doi.org/10.1109/cac48633.2019.8996624.

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Gopalakrishnan, Vishnu, Trent Nester, Juma Mgumbwa e Werner Holtzhausen. "Harvesting tailings from an active tailings storage facility: success and challenges – Frog’s Leg mine, Evolution Mining". In 21st International Seminar on Paste and Thickened Tailings. Australian Centre for Geomechanics, Perth, 2018. http://dx.doi.org/10.36487/acg_rep/1805_26_gopalakrishnan.

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